Akizuki Rokurōta was born as a child of Tokugawa Ieyasu, but since he is a twin with Tokugawa Iemitsu he is not allowed an official place within the Tokugawa family. Sent away as an adopted son, he continues his wandering journey. One day, he accidentally encounters Toyotomi Hideyori's son Toyotomi Hideya, his mother Katsura-no-miya Renko and their maidservant Sasaka, survivors of the Shogunate attack on Osaka Castle years before who are now fleeing from their refuge in Kyoto. The Tokugawa Shogunate and Yagyū clan are trying to capture or kill them, while on the other hand villains want to use them. Akizuki Rokurōta decides to protect them from both sides.